A Review for Antimicrobial Peptides with Anticancer Properties: Re-purposing of Potential Anticancer Agents

Abstract In recent years, various research on cancer treatment has achieved significant progress. However, some of these treatments remain disputable because of the emergence and development of drug resistance, and the toxic side effects that were brought about by the lack of selectivity displayed by the treatments. Hence, there is considerable interest in a new class of anticancer molecules that is currently still under investigation termed the cationic antimicrobial peptides (AMPs). AMPs are a group of pervasive components of the innate immunity which can be found throughout all classes of life. The small innate peptides cover a broad spectrum of antibacterial activities due to their electrostatic interactions with the negatively charged bacterial membrane. Compared with normal cells, cancer cells have increased proportions of negatively charged molecules, including phosphatidylserine, glycoproteins, and glycolipids, on the outer plasma membrane. This provides an opportunity for exploiting the interaction between AMPs and negatively charged cell membranes in developing unconventional anticancer strategies. Some AMPs may also be categorized into a group of potential anticancer agents called cationic anticancer peptides (ACPs) due to their relative selectivity in cell membrane penetration and lysis, which is similar to their interaction with bacterial membranes. Several examples of ACPs that are used in tumor therapy for their ability in penetrating or lysing tumor cell membrane will be reviewed in this paper, along with a discussion on the recent advances and challenges in the application of ACPs.